胜坨油田二区沙河街组二段三角洲储层微观特征

MICROCHARACTERISTICS OF DELTA RESERVOIR IN SECOND MEMBER OF SHAHEJIE FORMATION AT SECOND DISTRICT OF SHENGTUO OILFIELD

胜坨油田二区沙河街组二段（Ｅｓ２）三角洲储层以中细砂岩、粉砂岩为主，储层的埋藏较浅，成岩作用较弱，常见压实、胶结和溶解作用，粘土矿物的转化作用也较普遍，属于早成岩期的Ｂ亚期。储层的粒间孔隙发育，以中孔中细喉结构为主，孔喉参数变化范围较大，储层成岩和孔隙结构的非均质性较强。注水开发加大了不同相带的砂体成岩和孔隙结构的差异。

The diagenesis evolution and pore structures of delta reservoir in second member of Shahejie formation in second district of Shengtuo oilfield are studied. The result makes it clear that the buried depth of reservoir is more shallow, diagenesis is weak and the reservoir belongs to the second B period of early diagenetic period. Reservoir has a lot of intergranular pores and mean pores and mean thin throat structures. Because of great changes of pore and throat parameters, the reservoir microheterogenity is high, and water injection development makes it increasing because of the increase of diagenesis evolution and pore structures.